linux-dev/arch/powerpc/platforms/microwatt, branch linus/master

powerpc/microwatt: add POWER9_CPU, clear PPC_64S_HASH_MMU

2021-12-09T11:41:16Z

Microwatt implements a subset of ISA v3.0 (which is equivalent to the POWER9_CPU option). It is radix-only, so does not require hash MMU support. This saves 20kB compressed dtbImage and 56kB vmlinux size. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20211201144153.2456614-19-npiggin@gmail.com

powerpc/64s: Make hash MMU support configurable

2021-12-09T11:40:24Z

This adds Kconfig selection which allows 64s hash MMU support to be disabled. It can be disabled if radix support is enabled, the minimum supported CPU type is POWER9 (or higher), and KVM is not selected. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20211201144153.2456614-17-npiggin@gmail.com

powerpc: Rename PPC_NATIVE to PPC_HASH_MMU_NATIVE

2021-12-02T11:57:22Z

PPC_NATIVE now only controls the native HPT code, so rename it to be more descriptive. Restrict it to Book3S only. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20211201144153.2456614-3-npiggin@gmail.com

powerpc/microwatt: Make microwatt_get_random_darn() static

2021-11-25T00:25:34Z

Make microwatt_get_random_darn() static, because it can be. Reported-by: kernel test robot Signed-off-by: Michael Ellerman Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20211118004415.1706863-1-mpe@ellerman.id.au

powerpc/microwatt: Add support for hardware random number generator

2021-06-21T11:16:32Z

Microwatt's hardware RNG is accessed using the DARN instruction. Signed-off-by: Paul Mackerras Reviewed-by: Nicholas Piggin Reviewed-by: Segher Boessenkool Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/YMwXPHlV/ZleiQUY@thinks.paulus.ozlabs.org

powerpc/microwatt: Use standard 16550 UART for console

2021-06-21T11:16:31Z

This adds support to the Microwatt platform to use the standard 16550-style UART which available in the standalone Microwatt FPGA. Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Paul Mackerras Reviewed-by: Segher Boessenkool Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/YMwXGCTzedpQje7r@thinks.paulus.ozlabs.org

powerpc/xics: Add a native ICS backend for microwatt

2021-06-21T11:15:58Z

This is a simple native ICS backend that matches the layout of the Microwatt implementation of ICS. Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Paul Mackerras Reviewed-by: Segher Boessenkool [mpe: Add empty ics_native_init() to unbreak non-microwatt builds] Signed-off-by: Michael Ellerman fixup-ics Link: https://lore.kernel.org/r/YMwW8cxrwB2W5EUN@thinks.paulus.ozlabs.org

powerpc/microwatt: Populate platform bus from device-tree

2021-06-21T11:15:26Z

Just like any other embedded platform. Add an empty soc node. Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Paul Mackerras Reviewed-by: Segher Boessenkool Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/YMwWx98+PMibZq/G@thinks.paulus.ozlabs.org

powerpc: Add Microwatt platform

2021-06-21T11:15:26Z

Microwatt is a FPGA-based implementation of the Power ISA. It currently only implements little-endian 64-bit mode, and does not (yet) support SMP, VMX, VSX or transactional memory. It has an optional FPU, and an optional MMU (required for running Linux, obviously) which implements a configurable radix tree but not hypervisor mode or nested radix translation. This adds a new machine type to support FPGA-based SoCs with a Microwatt core. CONFIG_MATH_EMULATION can be selected for Microwatt SOCs which don't have the FPU. Signed-off-by: Paul Mackerras Reviewed-by: Nicholas Piggin Reviewed-by: Segher Boessenkool Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/YMwWbZVREsVug9R0@thinks.paulus.ozlabs.org